Account numbers on credit cards have meaning

That seemingly random collection of numbers on the front of a credit card actually does mean something. You just need to know how to decipher it.

Mark Williams, The Columbus Dispatch

That seemingly random collection of numbers on the front of a credit card actually does mean something. You just need to know how to decipher it.

In the same way that the Vehicle Identification Number on a car identifies the make, model and other information, the numbers tell plenty about what kind of card you’re packing in your wallet and who you are.

“It’s not 16 random numbers all put into a bingo machine and turned around,” said Bill Hardekopf, CEO of LowCards.com, which tracks credit cards. “Each one has a specific meaning. ... It helps to differentiate your card from every other card out there.”

Credit cards can have up to 19 digits. American Express cards have 15, and Visa, MasterCard and Discover have 16, says CreditCards.com. Each issuer has at least 1 trillion possible account numbers.

All credit cards are similar in size and virtually all are made of plastic because of a group called the International Organization for Standardization, an independent group that sets voluntary standards for products, services and systems.

On a 16-digit credit card, the first six numbers identify the card issuer. The next nine are the account number, similar to a checking-account number. The last digit is the only one that is random.

Start with the first digit on the card. That number identifies the industry of the card.

Cards that begin with a 1 or 2 represent the airline industry. Travel and entertainment cards, including American Express and Diners Club, start with a 3.

The numbers 4 and 5 represent financial and banking cards. Visa cards start with a 4, and MasterCard cards begin with a 5.

The number 6 is for merchandising and banking cards and includes Discover cards and department-store cards. Gasoline credit cards start with a 7.

Following the first number are the numbers that identify the bank that issued the card.

The last number, the only one that is randomly selected, is called the “check digit” and comes from an algorithm created by IBM scientist Hans Peter Luhn in 1954, says LowCards.com.

Originally, the idea of the “check digit” was to protect against human error back when credit-card numbers would have been entered manually, says CreditCards.com. Today, it acts as more of a way to deter thieves from inventing credit-card numbers.

If cards don’t move through the algorithm correctly, the transaction is blocked before it reaches the card issuer for authorization, said Matt Schulz, senior industry analyst for CreditCards.com.

“We’re all thinking about fraud these days. It’s an interesting fraud-detective device that predates the computer. It’s kind of an old-school formula that still works and is relied on,” he said.

The numbers on debit cards work similarly.

In addition to the “check digit,” credit cards come with a three- or four-digit security code on either the front or the back of cards that is supposed to help protect consumers making online or mail-order transactions.

Card security has become more of an issue since a series of data breaches at retailers that has exposed the personal information of millions of Americans.

Schulz said card companies are moving to install chips on cards that make it harder to counterfeit the card and expose cardholders in the event of a data breach. At the same time, they are pushing retailers to install the technology to read these cards by making them liable for losses tied to fraud beginning in October 2015.

The magnetic strip will remain on the back of the card until chip technology is deployed.

In the future, the industry likely will require consumers to use a personal identification number, as opposed to signing for purchases, in conjunction with the cards as is done in much of Europe today, Schulz said. Using a number reduces the worry of a consumer’s signature being forged.

Ultimately, the big question with credit cards in the coming years will be with the use of smartphones, he said. The phones will be able to incorporate a consumer’s credit-card information to make purchases.

“It’s a question of what happens with mobile,” he said. “That’s kind of the next frontier.”